Based on where you are from, different countries have different terms for "storm drain".

Subject to where you are from, different countries have different terms for "storm drain".
Accordingly to Wikipedia, a storm drain is largely a tunnel that carry runoffs (rain) from urban areas. For a layman, it helps to think along the line of sewage system which works beneath our cities.
In the US, this is actually best known "storm drain" or "storm sewer".
In great britan, this is also known as "surface water drain" or "surface water sewer".
In Australia and New Zealand, it is commonly known as We all have been to a swimming pool at least a few times in our lifetime. .
And there it is, the next time you hear someone mentioning What is outdoor furniture? , "storm sewer", "surface water drain","surface water sewer" and "stormwater drain", congratulations, you know they talk about exactly the same thing.
Functions of storm drain include draining excess water (rain or storm water) and ground water from pavement, streets and carparks into rivers and streams to avoid flooding.
Although storm drains accomplish a amazing job of draining excess water from the urban areas, the inlets are essentially openings where left uncovered could be a danger to pedestrians. Left uncovered, rubbish will go into the storm drains and cause choking which can eventually end up with flooding.
To ensure storm drains serve their purposes while minimizing the risks posed to pedestrians and to prevent choking of the drains, drain covers (gratings) are employed to cover the inlets (openings) of the storm drains to accomplish the two purposes.
Over at Get the Best Results With Your Garden Design. , we specialize in steel reinforced drain covers (gratings) for your storm drains while preserving the aesthetic aspects of the architecture around the drain covers.